This invention relates to a device for indicating the degree of tilt of a vehicle headlamp beam and, more specifically, to a device having a bubble level formed by a liquid-filled vial with a gas bubble therein that coacts with a graduated scale to indicate the degree of tilt of the vial from horizontal.
Such an indicating device typically is mounted on the frame or other component of the headlamp assembly. At the vehicle assembly plant, the frame is tilted about a horizontal axis to establish proper aim of the headlamp beam in a vertical direction. Once this is achieved, the inclination of the vial is adjusted in order to "zero" the bubble and establish the preset position of the headlamp. If the headlamp subsequently becomes improperly aimed, the indicating device may be used to determine when the lamp has been adjusted back to the preset position.
Commonly assigned Denley U.S. application Ser. No. 08/085,650, filed Jun. 30, 1993 discloses a comparatively small and low cost indicating device in which the vial is molded integrally with a base adapted to be assembled in a relatively simple manner with a spring metal retaining bracket by virtue of a slip fit between the base and the bracket. The device is installed with a slip fit into a molded housing or platform on the frame of the headlamp. When so installed, cantilevered legs of the bracket bear resiliently against laterally spaced upper walls of the housing to help retain the device in assembled relation with the housing. By virtue of resiliently engaging the upper walls of the housing, the legs enable the use of an adjusting screw for changing the inclination of the vial. Because the spring legs must resiliently engage the upper walls of the housing in order to enable adjustment of the vial, the device is more or less limited in use to a specific type of housing.